Series 50 – Section 17.5 Defective Magnetic Switch

Section 17.5
Defective Magnetic Switch

To determine if a defective magnetic switch is causing starting difficulty:‪

1. Start engine.
2. Clamp a heavy gauge battery jumper cable between the two large studs of the magnetic switch. see Figure "Basic Cranking Circuit" .
   

   Figure 1. Basic Cranking Circuit

3. Remove the jumper cable to shut down the engine.
   1. If the engine cranked with the jumper cable in place, the magnetic switch must be replaced; refer to "17.5.1 Magnetic Switch Replacement" .
   2. If the engine did not crank with the jumper cable in place, check the starter; refer to "17.6 Defective Starter" .

Section 17.5.1
Magnetic Switch Replacement

Perform the following for magnetic switch replacement:‪

1. Replace the magnetic switch; refer to OEM guidelines.
2. Verify magnetic switch replacement; refer to "17.5.1.1 Test Engine with Replaced Magnetic Switch" .

Section 17.5.1.1
Test Engine with Replaced Magnetic Switch

Perform the following to determine if the magnetic switch replacement resolved starting difficulty: ‪

1. Attempt to start and run the engine.
   1. If the engine starts and runs, no further troubleshooting is required. Shut the engine down.
   2. If the engine fails to start and run, check the starter; refer to "17.6 Defective Starter" .